I have Outlook 2013 installed in a 64-bit version. Besides my accounts with the Mailenable server I also have an Microsoft Exchange email account.

Since I have added the MS Exchange account, Outlook defaults this calendar as the default calendar. This is quite annoying when I import new calendar items through an internet link, as there is no way that I can select the calendar it should use. When I try to change the default calendar, I get the following error message: